Amanda Seyfried Defeats David Letterman in Dog Challenge on The Late Show (VIDEO)

Amanda Seyfried has appeared on The Late Show With David Letterman on Tuesday night, bringing her dog Finn on stage as well.

The "Mean Girls" actress came onto Letterman as part of a publicity tour to promote her new movie Lovelace, in which Seyfried plays adult film star, Linda Lovelace.

Seyfried boasted to Letterman that her dog was able to perform tricks, such as balance hamburgers on his head.

Letterman responded that he didn't believe it and challenged Seyfried to get him to perform the trick live on air to prove him wrong.

Letterman said: "A dog with raw or cooked meat on its head is going to go nuts and not sit with it on its head."

However, the actress confidently brought Finn forward and prepared the dog for the trick, before carefully placing the hamburger on his head. Finn barely flinched, and kept the burger sitting on his head easily.

Letterman admitted defeat: "That was stunning! I'm so sorry I doubted you and the dog."

The "Mama Mia" actress will be playing adult film star, Linda Lovelace, in her new movie, and she admitted to the talk show host that she felt uncomfortable allowing her father to see the film in full. However, she said that her family had been supportive of her latest film.

Seyfried said: "My dad is going to see it tonight. He's been super supportive. I'm sitting through it with him."

Seyfried has also been linked to rumors about starring as Anastasia Steele for the upcoming 50 Shades of Grey movie. However, various other actresses have also been touted as being considered and nothing official has been announced by those behind the upcoming film.